1. Field
The present invention relates to a development agent and an image forming apparatus employing the development agent.
2. Background Art
Latent images formed electrically or magnetically are typically rendered visible by an electrophotographic image forming apparatus using a development agent containing toner and toner carrier.
A latent electrostatic image is formed on an image bearing member and thereafter developed with toner charged by friction with the carrier to obtain a toner image.
The toner image is then transferred to a transfer medium, typically paper, and thereafter fixed thereon.
In the process in which the toner image is fixed on the transfer medium, a thermal fixing system such as a heating-roller fixing system and a heating-belt fixing system is generally used for greater energy efficiency.
There continues to be market demand for energy-efficient products.
One way to meet such demand is by employing toner having excellent low-temperature fixability and high-temperature stability.
JP-2010-77419-A describes resin particles containing crystalline resin.
The resin particulates are prepared using an aqueous medium.
The resin particulates have a melting heat maximum peak temperature (Ta) of from 40° C. to 100° C. and a ratio of the softening point to Ta (softening point/Ta) of from 0.8 to 1.55.
Also, the resin particles satisfy the following conditions 1: G′(Ta+20)=1×102 to 5×105 (Pa) and the condition 2: G″(Ta+20)=1×102 to 5×105 (Pa), where G′ represents storage elastic modulus and G″ represents loss elastic modulus.
JP-2007-199655-A describes toner containing organically modified inorganic laminate minerals in which organic ions are at least partially substituted for ions present between layers of the organically-modified inorganic laminate compound.
However, toner that contains crystalline resin and organically modified inorganic laminate minerals in which organic ions are at least partially substituted for ions present between layers of the organically modified inorganic laminate compound causes a problem in that the inorganic laminate minerals detached from the surface of the toner due to the stress generated by stirring within the development device contaminate the surface of toner carrier, so that the size of the charge on the toner carrier decreases.